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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Oncol.</journal-id>
<journal-title>Frontiers in Oncology</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Oncol.</abbrev-journal-title>
<issn pub-type="epub">2234-943X</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fonc.2025.1667226</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Oncology</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Prognosis of second primary oral squamous cell carcinoma after hematologic malignancy: a retrospective cohort analysis</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" equal-contrib="yes">
<name>
<surname>Yu</surname>
<given-names>Huajiao</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="author-notes" rid="fn003">
<sup>&#x2020;</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/formal-analysis/"/>
<role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/>
<role content-type="https://credit.niso.org/contributor-roles/visualization/"/>
<role content-type="https://credit.niso.org/contributor-roles/validation/"/>
</contrib>
<contrib contrib-type="author" equal-contrib="yes">
<name>
<surname>Li</surname>
<given-names>Bo</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="author-notes" rid="fn003">
<sup>&#x2020;</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/formal-analysis/"/>
<role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/>
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</contrib>
<contrib contrib-type="author">
<name>
<surname>Huang</surname>
<given-names>Yu</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/>
<role content-type="https://credit.niso.org/contributor-roles/data-curation/"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Zhang</surname>
<given-names>Xue</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/>
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</contrib>
<contrib contrib-type="author">
<name>
<surname>Zhou</surname>
<given-names>Hanchen</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<role content-type="https://credit.niso.org/contributor-roles/writing-original-draft/"/>
<role content-type="https://credit.niso.org/contributor-roles/data-curation/"/>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Feng</surname>
<given-names>Zhien</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="author-notes" rid="fn001">
<sup>*</sup>
</xref>
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<role content-type="https://credit.niso.org/contributor-roles/conceptualization/"/>
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</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Han</surname>
<given-names>Zhengxue</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="author-notes" rid="fn001">
<sup>*</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/2450437/overview"/>
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<aff id="aff1">
<sup>1</sup>
<institution>Department of Oral and Maxillofacial-Head and Neck Oncology, Beijing Stomatological Hospital, Capital Medical University</institution>, <addr-line>Beijing</addr-line>,&#xa0;<country>China</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Department of Oral and Maxillofacial Surgery, Affiliated Hospital of Inner Mongolia Medical University</institution>, <addr-line>Hohhot, Inner Mongolia</addr-line>,&#xa0;<country>China</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>Edited by: <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/926654/overview">Cheng Wang</ext-link>, Sun Yat-sen University, China</p>
</fn>
<fn fn-type="edited-by">
<p>Reviewed by: <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/1746041/overview">Wei Han</ext-link>, Nanjing University, China</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/3151715/overview">Jiannan Liu</ext-link>, Shanghai Jiao Tong University, China</p>
</fn>
<fn fn-type="corresp" id="fn001">
<p>*Correspondence: Zhengxue Han, <email xlink:href="mailto:Hanzx1989@163.com">Hanzx1989@163.com</email>; Zhien Feng, <email xlink:href="mailto:jyfzhen@mail.ccmu.edu.cn">jyfzhen@mail.ccmu.edu.cn</email>
</p>
</fn>
<fn fn-type="equal" id="fn003">
<p>&#x2020;These authors have contributed equally to this work</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>03</day>
<month>09</month>
<year>2025</year>
</pub-date>
<pub-date pub-type="collection">
<year>2025</year>
</pub-date>
<volume>15</volume>
<elocation-id>1667226</elocation-id>
<history>
<date date-type="received">
<day>16</day>
<month>07</month>
<year>2025</year>
</date>
<date date-type="accepted">
<day>18</day>
<month>08</month>
<year>2025</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2025 Yu, Li, Huang, Zhang, Zhou, Feng and Han.</copyright-statement>
<copyright-year>2025</copyright-year>
<copyright-holder>Yu, Li, Huang, Zhang, Zhou, Feng and Han</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
</license>
</permissions>
<abstract>
<sec>
<title>Backgrounds</title>
<p>Prognosis and optimal management strategies of second primary oral squamous cell carcinoma (OSCC) following a history of hematologic malignancies (HM) remain uncertain. We investigated whether HM history affects OSCC outcomes or necessitates treatment modifications.</p>
</sec>
<sec>
<title>Patients and methods</title>
<p>This retrospective cohort study included 2486 OSCC patients: 14 with OSCC as a second primary malignancy post-HM (SPM group) and 2472 with primary OSCC (non-SPM group). Using propensity score matching (PSM), we created two cohorts: 1:17 (13 SPM vs 232 non-SPM) and 1:3 (13 SPM vs 38 non-SPM). Outcomes were disease-free survival (DFS), overall survival (OS), and disease-specific survival (DSS). Survival differences were analyzed using log-rank tests. Multivariate Cox regression identified prognostic predictors.</p>
</sec>
<sec>
<title>Results</title>
<p>No significant survival differences existed between SPM and non-SPM groups in either cohort (1:17: DFS 53.8% vs 68.9%, p=0.102; OS 69.2% vs 81.3%, p=0.170; DSS 69.2% vs 82.2%, p=0.147. 1:3: DFS 53.8% vs 63.2%, p=0.302; OS 69.2% vs 76.3%, p=0.532; DSS 69.2% vs 78.9%, p=0.430). Cox regression identified independent predictors: DFS: Age (p=0.001), T stage (p&lt;0.001), N stage (p&lt;0.001); OS and DSS: Age (p&lt;0.001), T stage (p&lt;0.001), N stage (p&lt;0.001), pathological grade (p&lt;0.001), prior HM was not an independent predictor.</p>
</sec>
<sec>
<title>Conclusions</title>
<p>A history of HM does not independently predict the prognosis of second primary OSCC nor necessitate modifications to standard OSCC treatment.</p>
</sec>
</abstract>
<kwd-group>
<kwd>oral squamous cell carcinoma</kwd>
<kwd>hematologic malignancy</kwd>
<kwd>second primary malignancy</kwd>
<kwd>prognosis</kwd>
<kwd>surgical treatment</kwd>
</kwd-group>
<counts>
<fig-count count="4"/>
<table-count count="3"/>
<equation-count count="0"/>
<ref-count count="28"/>
<page-count count="8"/>
<word-count count="2900"/>
</counts>
<custom-meta-wrap>
<custom-meta>
<meta-name>section-in-acceptance</meta-name>
<meta-value>Head and Neck Cancer</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<sec id="s1" sec-type="intro">
<title>Introduction</title>
<p>Oral squamous cell carcinoma (OSCC) is one of the most prevalent head and neck malignancies, accounting for over 90% of oral cancers (<xref ref-type="bibr" rid="B1">1</xref>, <xref ref-type="bibr" rid="B2">2</xref>). Despite advances in surgical and adjuvant therapies, its 5-year survival rate remains around 50% (<xref ref-type="bibr" rid="B3">3</xref>, <xref ref-type="bibr" rid="B4">4</xref>). Tumor prognosis is influenced by a complex interplay of clinical, biological, and systemic factors (<xref ref-type="bibr" rid="B5">5</xref>&#x2013;<xref ref-type="bibr" rid="B7">7</xref>). Underlying systemic diseases may profoundly impact cancer development, treatment efficacy, and outcomes (<xref ref-type="bibr" rid="B8">8</xref>&#x2013;<xref ref-type="bibr" rid="B10">10</xref>).</p>
<p>Among systemic comorbidities, prior malignancies represent a distinct clinical entity (<xref ref-type="bibr" rid="B11">11</xref>, <xref ref-type="bibr" rid="B12">12</xref>). In patients with dual primary tumors, prognosis may be affected by the biological characteristics of both malignancies, cumulative treatment-related toxicities, immune microenvironment remodeling (<xref ref-type="bibr" rid="B13">13</xref>), and molecular interactions. Patients with hematologic malignancies (HM), such as leukemia or lymphoma, face elevated risks of secondary solid tumors, including OSCC, primarily due to factors such as treatment-induced DNA damage (<xref ref-type="bibr" rid="B14">14</xref>) and immune microenvironment alterations (<xref ref-type="bibr" rid="B13">13</xref>). Notably, persistent immunosuppression (<xref ref-type="bibr" rid="B15">15</xref>) and chronic inflammation (<xref ref-type="bibr" rid="B16">16</xref>) in these individuals may promote a tumor-permissive microenvironment.</p>
<p>Although second primary malignancies (SPM) in cancer survivors, particularly those with prior HM, are increasingly studied, the independent prognostic impact of HM history on subsequent OSCC remains not well characterized. These patients often present compounded challenges from cumulative immunosuppression (<xref ref-type="bibr" rid="B15">15</xref>), impaired bone marrow function, and heightened susceptibility to therapy-related carcinogenesis (<xref ref-type="bibr" rid="B14">14</xref>).</p>
<p>This study aims to compare OSCC prognosis between patients with and without a history of hematologic malignancy, specifically examining whether well-controlled prior HM confers additional risk. We further seek to evaluate whether standard OSCC treatment protocols adequately meet the needs of this subgroup or require modification. Our findings are expected to inform clinical decision-making and guide treatment optimization for patients burdened by complex oncologic histories.</p>
</sec>
<sec id="s2">
<title>Patients and methods</title>
<sec id="s2_1">
<title>Participants</title>
<p>This research was conducted in accordance with the World Medical Association&#x2019;s Declaration of Helsinki (2002 revision). Ethical approval was obtained from the Institutional Review Board of the Beijing Stomatological Hospital, Capital Medical University (approval number: CMUSH-IRB-KJ-PJ-2022-38).</p>
<p>The study cohort comprised 2486 patients with OSCC who received treatment at the Department of Oral and Maxillofacial-Head and Neck Oncology, Beijing Stomatological Hospital, Capital Medical University from January 2000 to December 2021.</p>
</sec>
<sec id="s2_2">
<title>Eligibility criteria</title>
<p>The tumors were reclassified in accordance with the 8th edition of the UICC/AJCC classification system, utilizing the initial clinical descriptions as the basis for restaging. The criteria for patient selection were as follows: (1) histopathological confirmation of malignant tumor, (2) the site of tumor is the oral and maxillofacial region. The exclusion criteria are as follows: (1) distant metastasis, (2) no surgical treatment received, (3) the lesion site is located in the oropharynx, jawbone and glands, (4) pathologically confirmed as non-squamous cell carcinoma.</p>
</sec>
<sec id="s2_3">
<title>Treatments</title>
<p>All patients in this study received surgical treatment and adjuvant therapy according to different stages and the regimens recommended by the NCCN guidelines, repair and reconstruction was performed if necessary.</p>
</sec>
<sec id="s2_4">
<title>Follow-up</title>
<p>All the enrolled patients received regular follow-ups. The follow-up for OSCC was conducted by the specialist of our center, while the follow-up for HM was carried out by the hematology physicians. All the follow-up results were recorded in the patients&#x2019; medical records, and the frequency for each patient is once every 3&#x2013;6 months.</p>
</sec>
<sec id="s2_5">
<title>Definitions</title>
<p>In this study, the SPM group was defined as patients whose first primary malignancy was a hematologic malignancy (HM) and whose second primary malignancy was OSCC. Patients presenting with OSCC as their first primary malignancy were classified as non-SPM. Disease-free survival (DFS), overall survival (OS) and disease-specific survival (DSS) were used as outcome variables to evaluate prognosis. The interval from the initial surgery to recurrence or death was used to calculate the DFS. OS was defined from the time of the initial surgery to death or the last follow-up. DSS was defined from the time of the initial surgery to the death cause from cancer or the last follow-up.</p>
</sec>
<sec id="s2_6">
<title>Data analyses</title>
<p>Descriptive statistics were compiled to present the data in terms of frequencies and percentages. Comparative analysis of baseline demographic characteristics was conducted using the chi-square test for categorical variables. The Kaplan-Meier survival analysis was utilized to assess DFS, OS and DSS, with the log-rank test employed to evaluate the significance of differences between groups. Potential predictors were examined through cox proportional hazards regression analysis. All statistical tests were two-sided, with a significance level set at p&lt;0.05. The statistical analyses were performed using SPSS software (version 21.0 for Windows) and R (version 4.3.1 for Windows).</p>
<p>To minimize selection bias, propensity score matching (PSM) was employed to balance the different groups in terms of baseline covariates, PSM could reduce confounding factors and improve comparability among different group, SPSS was used to implement PSM. We set the caliper value to 0.1 and the matching ratio of SPM group and non-SPM group to 1:17 (the sample size calculation is completed through PASS). Due to the sample size, a high proportion of matching may affect the results. Therefore, a matching ratio of 1:3 is also used for double testing of the results.</p>
</sec>
</sec>
<sec id="s3" sec-type="results">
<title>Results</title>
<sec id="s3_1">
<title>Patients</title>
<p>A total of 3262 patients with oral and maxillofacial malignant tumors who met the study time were included, through the inclusion and exclusion criteria for screening, a total of 2486 patients were finally included in this study, among which 14 cases (0.6%) were in the SPM group and 2472 cases (99.4%) were in the non-SPM group (<xref ref-type="fig" rid="f1">
<bold>Figure&#xa0;1</bold>
</xref>).</p>
<fig id="f1" position="float">
<label>Figure&#xa0;1</label>
<caption>
<p>Flowchart for screening enrolled patients. Out of the 3262 patients, 2486 met the inclusion criteria. Among them, 14 were in the SPM group and 2472 were in the non-SPM group.</p>
</caption>
<graphic mimetype="image" mime-subtype="tiff" xlink:href="fonc-15-1667226-g001.tif">
<alt-text content-type="machine-generated">Flowchart showing patient selection for a study. Starting with 3,262 oral and maxillofacial tumors, 2,873 were squamous cell carcinoma. After exclusions, 2,571 were oral cavity malignant tumors. Enrolled patients totaled 2,486, divided into 14 in the SPM group and 2,472 in the non-SPM group. Other categories include non-squamous cell carcinoma, oropharynx, jawbone, and gland sites (302), and distant metastasis with no surgery (85).</alt-text>
</graphic>
</fig>
<p>Among the 2486 patients, 1428 were male (57.4%) and 1058 were female (42.6%). Mean age was 59.6 years, with a slight predominance of younger patients (1259, 50.6%) over older patients (1227, 49.4%). The tongue was the most common site in the overall situation, with a total of 1084 cases (43.6%), followed by the gums (684, 27.5%), buccal (418, 16.8%), floor of the mouth (237, 9.5%), and hard palate (63, 2.5%). The distribution of T stages is as follows: 21 cases (0.8%) in Tis stage, 563 cases (22.7%) in T1 stage, 854 cases (34.3%) in T2 stage, 313 cases (12.6%) in T3 stage, 663 cases (26.7%) in T4a stage, and 72 cases (2.9%) in T4b stage; Most patients were at the N0 stage (1656 cases, 66.6%) at the time of diagnosis, followed by the N2 stage (459 cases, 18.4%), the N1 stage (327 cases, 13.2%), and the N3 stage (44 cases, 1.8%). Among them, 1016 patients had a history of smoking (40.9%), and 1470 patients had no history of smoking (59.1%). 817 patients had a history of alcohol consumption, while 1669 patients had no history of alcohol consumption. The survival curve of the total queue is shown in <xref ref-type="fig" rid="f2">
<bold>Figure&#xa0;2</bold>
</xref>.</p>
<fig id="f2" position="float">
<label>Figure&#xa0;2</label>
<caption>
<p>Survival curves of all enrolled patients: <bold>(A)</bold> DFS; <bold>(B)</bold> OS; <bold>(C)</bold> DSS.</p>
</caption>
<graphic mimetype="image" mime-subtype="tiff" xlink:href="fonc-15-1667226-g002.tif">
<alt-text content-type="machine-generated">Kaplan-Meier survival curves showing survival probabilities over time in months for three subgroups: (A) Blue curve, (B) Red curve, and (C) Green curve. Each plot includes censored data points marked with crosses. Survival probability generally decreases over time in all graphs.</alt-text>
</graphic>
</fig>
</sec>
<sec id="s3_2">
<title>Baseline characteristics and disease management in the SPM cohort</title>
<p>The SPM cohort (n=14) comprised 9 males and 5 females. Primary hematologic malignancies included leukemia (n=9) and lymphoma (n=5), the treatment of the first primary malignancy of patients in the SPM group includes bone marrow transplantation, immunosuppression, chemotherapy, radiotherapy, and surgical therapy, which are combined into different treatment regimens. Mean age at first primary malignancy diagnosis was 36.6 years and 50.1 years for SPM diagnosis. SPM sites included tongue (n=6), buccal (n=4), gum (n=3), and hard palate (n=1). Tumor staging revealed Tis (n=1), T1 (n=3), T2 (n=7), T3 (n=1), and T4a (n=2) disease and all patients underwent surgical treatment for OSCC, one patient received adjuvant radiotherapy. All patients had negative lymph nodes (N0 stage). Seven patients reported tobacco use history and four reported alcohol use history (<xref ref-type="table" rid="T1">
<bold>Table&#xa0;1</bold>
</xref>).</p>
<table-wrap id="T1" position="float">
<label>Table&#xa0;1</label>
<caption>
<p>Basic information of patients in the SPM group.</p>
</caption>
<table frame="hsides">
<thead>
<tr>
<th valign="middle" align="center">Number</th>
<th valign="middle" align="center">Gender</th>
<th valign="middle" align="center">FM</th>
<th valign="middle" align="center">Age (FM)</th>
<th valign="middle" align="center">Treatment (FM)</th>
<th valign="middle" align="center">Age (SM)</th>
<th valign="middle" align="center">Site (SM)</th>
<th valign="middle" align="center">T stage</th>
<th valign="middle" align="center">N stage</th>
<th valign="middle" align="center">Tobacco/Alcohol</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="center">Patient 1</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">35</td>
<td valign="middle" align="center">BMT+IST+CT</td>
<td valign="middle" align="center">50</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T3</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 2</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">40</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">48</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/Yes</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 3</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">33</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">41</td>
<td valign="middle" align="center">Buccal</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 4</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">34</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">43</td>
<td valign="middle" align="center">Buccal</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 5</td>
<td valign="middle" align="center">Female</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">14</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">16</td>
<td valign="middle" align="center">Buccal</td>
<td valign="middle" align="center">T1</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 6</td>
<td valign="middle" align="center">Female</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">18</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">27</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 7</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">33</td>
<td valign="middle" align="center">BMT+CT</td>
<td valign="middle" align="center">47</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/Yes</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 8</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">38</td>
<td valign="middle" align="center">BMT+IST+CT</td>
<td valign="middle" align="center">50</td>
<td valign="middle" align="center">Buccal</td>
<td valign="middle" align="center">Tis</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/Yes</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 9</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Lymphoma</td>
<td valign="middle" align="center">59</td>
<td valign="middle" align="center">CT</td>
<td valign="middle" align="center">69</td>
<td valign="middle" align="center">Hard Palate</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 10</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Lymphoma</td>
<td valign="middle" align="center">53</td>
<td valign="middle" align="center">CT+RT</td>
<td valign="middle" align="center">63</td>
<td valign="middle" align="center">Gum</td>
<td valign="middle" align="center">T4a</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/Yes</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 11</td>
<td valign="middle" align="center">Female</td>
<td valign="middle" align="center">Lymphoma</td>
<td valign="middle" align="center">70</td>
<td valign="middle" align="center">CT+RT</td>
<td valign="middle" align="center">76</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T1</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 12</td>
<td valign="middle" align="center">Male</td>
<td valign="middle" align="center">Lymphoma</td>
<td valign="middle" align="center">28</td>
<td valign="middle" align="center">ST+CT</td>
<td valign="middle" align="center">39</td>
<td valign="middle" align="center">Gum</td>
<td valign="middle" align="center">T4a</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">Yes/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 13</td>
<td valign="middle" align="center">Female</td>
<td valign="middle" align="center">Lymphoma</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center">ST+CT+RT</td>
<td valign="middle" align="center">66</td>
<td valign="middle" align="center">Tongue</td>
<td valign="middle" align="center">T1</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
<tr>
<td valign="middle" align="center">Patient 14</td>
<td valign="middle" align="center">Female</td>
<td valign="middle" align="center">Leukemia</td>
<td valign="middle" align="center">50</td>
<td valign="middle" align="center">CT</td>
<td valign="middle" align="center">66</td>
<td valign="middle" align="center">Gum</td>
<td valign="middle" align="center">T2</td>
<td valign="middle" align="center">N0</td>
<td valign="middle" align="center">No/No</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn>
<p>FM, first malignance; SM, second malignance; BMT, bone marrow transplantation; IST, immunosuppressive therapy; CT, chemotherapy; RT, radiotherapy; ST, surgical treatment.</p>
</fn>
</table-wrap-foot>
</table-wrap>
</sec>
<sec id="s3_3">
<title>Baseline characteristics after propensity score matching</title>
<p>PSM was performed using 1:17 and 1:3 ratio to screen out comparable datasets. Ultimately, in 1:17 matching a total of 232 patients were included in the matching cohort, with 13 cases in the SPM group and 219 cases in the non-SPM group, the baseline data are shown in <xref ref-type="table" rid="T2">
<bold>Table&#xa0;2</bold>
</xref>. In another group of pairs matched at a ratio of 1:3, a total of 51 patients were included, including 13 in the SPM group and 38 in the non-SPM group (<xref ref-type="table" rid="T3">
<bold>Table&#xa0;3</bold>
</xref>).</p>
<table-wrap id="T2" position="float">
<label>Table&#xa0;2</label>
<caption>
<p>Patient characteristics after propensity score matching by 1:17.</p>
</caption>
<table frame="hsides">
<thead>
<tr>
<th valign="middle" align="center">Variable</th>
<th valign="middle" align="center">Non-SPM group (n=219)</th>
<th valign="middle" align="center">SPM group (n=13)</th>
<th valign="middle" align="center">p-value</th>
<th valign="middle" align="center">SMD</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left">Age</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.681</td>
<td valign="middle" align="center">0.077</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;&#x2264;60</td>
<td valign="middle" align="center">122</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;&gt;60</td>
<td valign="middle" align="center">97</td>
<td valign="middle" align="center">5</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Gender</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.410</td>
<td valign="middle" align="center">0.004</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Male</td>
<td valign="middle" align="center">109</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Female</td>
<td valign="middle" align="center">110</td>
<td valign="middle" align="center">5</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Site</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.778</td>
<td valign="middle" align="center">0.123</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Tongue</td>
<td valign="middle" align="center">94</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Gum</td>
<td valign="middle" align="center">75</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Buccal</td>
<td valign="middle" align="center">42</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Hard palate</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center">1</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">T stage</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.959</td>
<td valign="middle" align="center">0.022</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T1</td>
<td valign="middle" align="center">51</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T2</td>
<td valign="middle" align="center">103</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T3</td>
<td valign="middle" align="center">21</td>
<td valign="middle" align="center">1</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T4</td>
<td valign="middle" align="center">44</td>
<td valign="middle" align="center">2</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Pathological grade</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.507</td>
<td valign="middle" align="center">0.086</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Well</td>
<td valign="middle" align="center">138</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;moderately</td>
<td valign="middle" align="center">81</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Tobacco use</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.382</td>
<td valign="middle" align="center">0.033</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Yes</td>
<td valign="middle" align="center">75</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;No</td>
<td valign="middle" align="center">144</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Alcohol use</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.813</td>
<td valign="middle" align="center">0.063</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Yes</td>
<td valign="middle" align="center">57</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;No</td>
<td valign="middle" align="center">162</td>
<td valign="middle" align="center">10</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
</tbody>
</table>
</table-wrap>
<table-wrap id="T3" position="float">
<label>Table&#xa0;3</label>
<caption>
<p>Patient characteristics after propensity score matching by 1:3.</p>
</caption>
<table frame="hsides">
<thead>
<tr>
<th valign="middle" align="center">Variable</th>
<th valign="middle" align="center">Non-SPM group (n=38)</th>
<th valign="middle" align="center">SPM group (n=13)</th>
<th valign="middle" align="center">p-value</th>
<th valign="middle" align="center">SMD</th>
</tr>
</thead>
<tbody>
<tr>
<td valign="middle" align="left">Age</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.577</td>
<td valign="middle" align="center">0.155</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;&#x2264;60</td>
<td valign="middle" align="center">20</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;&gt;60</td>
<td valign="middle" align="center">18</td>
<td valign="middle" align="center">5</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Gender</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.818</td>
<td valign="middle" align="center">0.103</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Male</td>
<td valign="middle" align="center">22</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Female</td>
<td valign="middle" align="center">16</td>
<td valign="middle" align="center">5</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Site</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.843</td>
<td valign="middle" align="center">0.120</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Tongue</td>
<td valign="middle" align="center">13</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Gum</td>
<td valign="middle" align="center">11</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Buccal</td>
<td valign="middle" align="center">12</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Hard palate</td>
<td valign="middle" align="center">2</td>
<td valign="middle" align="center">1</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">T stage</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.985</td>
<td valign="middle" align="center">&lt;0.100</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T1</td>
<td valign="middle" align="center">9</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T2</td>
<td valign="middle" align="center">20</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T3</td>
<td valign="middle" align="center">2</td>
<td valign="middle" align="center">1</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;T4</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center">2</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Pathological grade</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.799</td>
<td valign="middle" align="center">0.100</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Well</td>
<td valign="middle" align="center">22</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;moderately</td>
<td valign="middle" align="center">16</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Tobacco use</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.811</td>
<td valign="middle" align="center">&lt;0.100</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Yes</td>
<td valign="middle" align="center">19</td>
<td valign="middle" align="center">6</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;No</td>
<td valign="middle" align="center">19</td>
<td valign="middle" align="center">7</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">Alcohol use</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
<td valign="middle" align="center">0.878</td>
<td valign="middle" align="center">&lt;0.100</td>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;Yes</td>
<td valign="middle" align="center">8</td>
<td valign="middle" align="center">3</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
<tr>
<td valign="middle" align="left">&#x2003;No</td>
<td valign="middle" align="center">30</td>
<td valign="middle" align="center">10</td>
<td valign="middle" align="center"/>
<td valign="middle" align="center"/>
</tr>
</tbody>
</table>
</table-wrap>
</sec>
<sec id="s3_4">
<title>Comparable prognosis in SPM and non-SPM groups</title>
<p>Kaplan-Meier analysis revealed no significant prognostic differences between groups. In the 1:17 matched cohort, DFS (53.8% vs. 68.9%, p=0.102), OS (69.2% vs. 81.3%, p=0.170) and DSS (69.2% vs. 82.2%, p=0.147) did not show significant statistical differences in SPM group and non-SPM group (<xref ref-type="fig" rid="f3">
<bold>Figure&#xa0;3</bold>
</xref>). The similar results were obtained in 1:3 matching cohort, which indicated that DFS (53.8% vs. 63.2%, p=0.302), OS (69.2% vs. 76.3%, p=0.532) and DSS (69.2% vs. 78.9%, p=0.430), no significant statistical difference was observed between SPM group and non-SPM group (<xref ref-type="fig" rid="f4">
<bold>Figure&#xa0;4</bold>
</xref>). These results suggest that among patients with prior hematologic malignancies, OSCC as a second primary malignancy confers no significantly different prognosis compared to OSCC as a first primary malignancy.</p>
<fig id="f3" position="float">
<label>Figure&#xa0;3</label>
<caption>
<p>Kaplan-Meier survival analysis of the PSM cohort (1:17 matching ratio). No statistically significant differences were observed between SPM group and non-SPM group. <bold>(A)</bold> DFS: 53.8% vs. 68.9% (p=0.102); <bold>(B)</bold> OS: 69.2% vs. 81.3% (p=0.170); <bold>(C)</bold> DSS: 69.2% vs. 82.2% (p=0.147).</p>
</caption>
<graphic mimetype="image" mime-subtype="tiff" xlink:href="fonc-15-1667226-g003.tif">
<alt-text content-type="machine-generated">Three panels, labeled A, B, and C, each display survival curves comparing non-SPM and SPM groups over 200 months. All panels include curves, p-values, risk numbers, and censoring events. Panel A shows p=0.102, B shows p=0.170, and C shows p=0.147, all indicating survival probabilities over time.</alt-text>
</graphic>
</fig>
<fig id="f4" position="float">
<label>Figure&#xa0;4</label>
<caption>
<p>Kaplan-Meier survival analysis of the PSM cohort (1:3 matching ratio). No statistically significant differences were observed between SPM group and non-SPM group. <bold>(A)</bold> DFS: 53.8% vs. 63.2% (p=0. 0.302); <bold>(B)</bold> OS: 69.2% vs. 76.3% (p=0.532); <bold>(C)</bold> DSS: 69.2% vs. 78.9% (p=0.430).</p>
</caption>
<graphic mimetype="image" mime-subtype="tiff" xlink:href="fonc-15-1667226-g004.tif">
<alt-text content-type="machine-generated">Three panels (A, B, C) of survival curves display survival probability over time in months for two strata: non-SPM (blue) and SPM (red). Each panel includes a p-value and corresponding graphs for the number at risk and number of censorings. Panel A shows a p-value of 0.302, B of 0.532, and C of 0.430, with varying survival probabilities and changes over time across panels.</alt-text>
</graphic>
</fig>
</sec>
<sec id="s3_5">
<title>Independent predictors were screened through Cox regression analysis</title>
<p>Multivariable Cox proportional hazards regression was performed to identify independent prognostic factors across survival endpoints. The analysis established age as a consistent predictor for all outcomes, with significantly increased risk observed for DFS (p=0.001), OS (p&lt;0.001), and DSS (p&lt;0.001). Similarly, advanced T stage and N stage demonstrated strong independent associations with reduced survival across all three endpoints (p&lt;0.001 for each). Notably, pathological grade emerged as a powerful independent determinant for both OS (p&lt;0.001) and DSS (p&lt;0.001), suggesting its differential impact on survival outcomes (<xref ref-type="supplementary-material" rid="SM1">
<bold>Supplementary Table&#xa0;1</bold>
</xref>).</p>
</sec>
</sec>
<sec id="s4" sec-type="discussion">
<title>Discussion</title>
<p>The prognosis of OSCC is multifactorial, with systemic health status representing a key determinant. Among systemic comorbidities, a history of prior malignancy&#x2014;particularly HM&#x2014;constitutes a distinct clinical entity.</p>
<p>HM may influence the development and progression of SPMs. First, HM inherently induce systemic immune impairment, including T-cell dysfunction, diminished NK-cell activity, and compromised humoral immunity (<xref ref-type="bibr" rid="B17">17</xref>&#x2013;<xref ref-type="bibr" rid="B20">20</xref>), this significantly weakens immune surveillance against solid tumors (<xref ref-type="bibr" rid="B21">21</xref>, <xref ref-type="bibr" rid="B22">22</xref>). Second, HM treatments further impact SPM risk: conventional radiotherapy and chemotherapy regimens exacerbate immune injury, causing persistent lymphocyte subset imbalances. These therapies represent a double-edged sword&#x2014;while targeting malignant cells, they simultaneously inflict DNA damage on healthy tissues in a dose-dependent manner (<xref ref-type="bibr" rid="B23">23</xref>&#x2013;<xref ref-type="bibr" rid="B25">25</xref>). Additionally, the risk of SPM in HM patients after CART treatment should also be vigilant (<xref ref-type="bibr" rid="B26">26</xref>). Consequently, immune reconstitution failure may not only enhance tumor aggressiveness in second primary cancers but also diminish responsiveness to immunotherapy. Collectively, systemic immune dysregulation and chronic inflammation establish a tumor-promoting milieu.</p>
<p>HM survivors frequently exhibit persistent antigenic stimulation and inflammatory microenvironments that facilitate OSCC pathogenesis through multiple molecular pathways. The neutrophil-to-lymphocyte ratio, a validated systemic inflammation biomarker, demonstrates significant correlation with OSCC prognosis (<xref ref-type="bibr" rid="B27">27</xref>, <xref ref-type="bibr" rid="B28">28</xref>). In HM survivors, this pro-inflammatory state often persists due to underlying disease and prior therapies.</p>
<p>Importantly, the prognosis of HM patients developing into SPM is still not completely clear, and the reasons may be multi-faceted. On the one hand, the causes of SPM in HM patients are very complex. It may be related to the impact of the HM disease itself on the overall condition, or it may be related to the complex treatment plan of HM. On the other hand, such cases are usually few in number and it is difficult to complete effective statistical analysis.</p>
<p>Our large-sample cohort study specifically examined OSCC outcomes in patients with prior HM. While concerns historically existed regarding treatment planning for this population&#x2014;given potential HM-related comorbidities and uncertain prognosis&#x2014;our exploratory analysis provides clinical guidance. Current findings indicate that a history of well-controlled HM does not constitute an independent high-risk prognostic factor for OSCC. Thus, patients developing OSCC as SPM after HM should be considered for conventional OSCC therapy.</p>
<p>Study limitations include the relatively small SPM subgroup size, which constrains statistical power. Nevertheless, large-scale cohort analysis remains the optimal feasible approach. Future work will expand recruitment to strengthen these findings.</p>
</sec>
<sec id="s5" sec-type="conclusions">
<title>Conclusions</title>
<p>Following conventional OSCC therapy, no statistically significant difference in prognosis was observed between patients with OSCC as a second primary malignancy after HM and those with primary OSCC, indicating that treatment modification appears unnecessary for these patients.</p>
</sec>
</body>
<back>
<sec id="s6" sec-type="data-availability">
<title>Data availability statement</title>
<p>The original contributions presented in the study are included in the article/<xref ref-type="supplementary-material" rid="SM1">
<bold>Supplementary Material</bold>
</xref>. Further inquiries can be directed to the corresponding authors.</p>
</sec>
<sec id="s7" sec-type="ethics-statement">
<title>Ethics statement</title>
<p>The studies involving humans were approved by Institutional Review Board of the Beijing Stomatological Hospital, Capital Medical University. The studies were conducted in accordance with the local legislation and institutional requirements. Written informed consent for participation was not required from the participants or the participants&#x2019; legal guardians/next of kin in accordance with the national legislation and institutional requirements.</p>
</sec>
<sec id="s8" sec-type="author-contributions">
<title>Author contributions</title>
<p>HY: Formal analysis, Writing &#x2013; original draft, Visualization, Validation. BL: Formal analysis, Writing &#x2013; original draft, Validation, Investigation. YH: Writing &#x2013; original draft, Data curation. XZ: Writing &#x2013; original draft, Formal analysis. HZ: Writing &#x2013; original draft, Data curation. ZF: Writing &#x2013; review &amp; editing, Conceptualization, Supervision, Funding acquisition. ZH: Conceptualization, Methodology, Supervision, Resources, Funding acquisition, Writing &#x2013; review &amp; editing.</p>
</sec>
<sec id="s9" sec-type="funding-information">
<title>Funding</title>
<p>The author(s) declare that financial support was received for the research and/or publication of this article. The work was supported by National Natural Science Foundation of China (82370925).</p>
</sec>
<sec id="s10" sec-type="COI-statement">
<title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="s11" sec-type="ai-statement">
<title>Generative AI statement</title>
<p>The author(s) declare that no Generative AI was used in the creation of this manuscript.</p>
<p>Any alternative text (alt text) provided alongside figures in this article has been generated by Frontiers with the support of artificial intelligence and reasonable efforts have been made to ensure accuracy, including review by the authors wherever possible. If you identify any issues, please contact us.</p>
</sec>
<sec id="s12" sec-type="disclaimer">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
<sec id="s13" sec-type="supplementary-material">
<title>Supplementary material</title>
<p>The Supplementary Material for this article can be found online at: <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fonc.2025.1667226/full#supplementary-material">https://www.frontiersin.org/articles/10.3389/fonc.2025.1667226/full#supplementary-material</ext-link>
</p>
<supplementary-material xlink:href="Table1.docx" id="SM1" mimetype="application/vnd.openxmlformats-officedocument.wordprocessingml.document"/>
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